also coming up. remember the latest news and weather is on our website, cbssf.com. (explosions) >> pelley: tonight, bombs explod oston marathon. (screaming) >> run! >> pelley: it was horrible. the scene that you saw, it was freaking horrible. >> pelley: there was chaos at the finish line. >> it's so terrifying. it's so scary. and there was smoke and glass everywhere. >> pelley: at least two are dead, many dozens hurt. captioning sponsored by cbs this is the "cbs evening news" with scott pelley. >> pelley: and this is a special western edition. good evening. the hunt is on tonight for a killer. president obama has vowed to find and bring to justice whoever was behind the deadly terrorist attack today at the boston marathon. two bombs went off as dozens of runners were crossing the finish line. one explosion near the reviewing

stand injured bystanders and knocked some runners off their feet. and second later there was another blast just down the block. at least two people have been killed, more than 120 wounded and many of them are in critical condition at this hour. rescuers pulled the injured away in wheelchairs at one point. at least one bomb that did not explode was reportedly recovered at the scene but there is conflicting information about that as this story continues to develop in the evening. tonight downtown boston is essentially locked down. police have urged people to go home and avoid large crowds just to be safe. the attack came at the end of the boston marathon, one of the oldest and most famous of the world's marathons. a grueling 26-mile race into downtown boston ending on boylston street. we have a team of correspondents

covering every angle of the attack and we will begin tonight with terrell brown in boston. >> reporter: the explosion went off at the most crowded points of the race. 12 seconds later there was a second explosion just a couple blocks away. >> it's so terrifying. it's so scary. and it was so loud. >> i just walked away, 15 feet away, 20 feet and, you know, a bomb went off. and it knocked me to the ground and then, you know, everybody started running, panicking. >> reporter: jonathan elias from cbs boston station wbz was nearby. >> there are body parts. people have been blown apart. >> reporter: police rushed to assist victims tangled in debris and broken glass, some missing

limbs. bloody spectators were carried into the medical tent that had been set up to care for fatigued runners. >> there was some bad-looking people and i'm praying for all of them. we are all trying to put pressure on all the wounds for everybody, tourniquets and whatever we could do. it was chaos. >> reporter: runners were directed away from the chaos and people were ordered to stay clear of trash cans. >> reporter: edward davis is the boston police commissioner. >> people should be calm but they should understand that this is an ongoing event and they should understand that we need all the information that we can get available to us. >> pelley: terrell brown's report from boston tonight. there were more than 100 people still in the hospital, some of them as young as two, three, nine years old. some of those people are in critical condition. john miller has been talking

with his sources in law enforcement all afternoon long and, john, what can you tell us? >> well, one of those hundred people in the hospital is somebody they're interested in. this was an individual who witnesses just before the blast saw and thought was acting suspiciously and after the blast ran away. although we have to say if context a lot of people ran away. he was chased down and tackled, handed over to boston police and this is someone they are talking to now. he's suffering from burns. >> pelley: john, there's been conflicting reports about whether an unexploded bomb was discovered and defused by the police. what do you know about that? >> so you have the two devices that went off and then a number of packages that the bomb squad disrupted. we were told earlier today that one of those was a recovered device. right now there's a little bit walking back from that so we still have some reports that they recovered a device and we have some people saying it now appears that they did not. that would be unfortunate

because an intact device would give them a real jump start on clues about the makeup and maker of the bomb. >> pelley: there has been no claim of responsibility that we know of at this point. what does that tell you? >> well, it tells us that in an organized attack by a known pryce group what we've seen in the past, including the truck bomb that was placed in times square, that didn't go off, the claim of responsibility came at a time it was supposed to go off. so the point is usually they have a claim of responsibility that is ready to go off almost seamlessly. it suggests-- and, again, this is analysis, not fact-- that this may be the work of a lone wolf type operation where they might have attempted to claim responsibility later and we haven't heard that yet. >> pelley: we do not know at this point whether this was terrorism foreign or domestic. what will the f.b.i. do in these early hours? what kind of evidence are they looking for? >> what you're looking at here,

scott, is a different kind of marathon which is all hands in boston. the entire joint terrorism fact force and the entire rest of the boston field division of the f.b.i. have been called in and they have set up a case management system that will track every lead that's coming in. it will be searchable so that they don't have anything fall through the cracks and they're going to start running at this. they'll look at those bomb fragments, calls from the public, what comes into e-mail and they'll be looking at all of the intelligence from the 16 agencies and the intelligence community to see can we get a leg up and a direction. and, of course, they'll start with that individual they're talking to. >> pelley: john miller, thank you very much. some of the best coverage has come from our cbs news affiliate wbz, they have been on the story since the moment of the first explosion. jonathan elias was there when the bombs went off. john, can you tell us what you saw? >> reporter: scott, i was literally 30 feet away from when the bomb went off. we were sitting at the finish line, our backs two the

grandstand. in front of us was the finish line. it was such a joyous occasion with the runners finishing their 26.2 miles and they were coming across the line and we were high fiving them, applauding them, our photographer is a big fellow, he stood up over everybody and suddenly this explosion happened across the street. a huge white cloud came up off the sidewalk. initially everybody froze, everybody, including those in the grandstand not knowing what it was. then the second explosion went off two blocks away not more than 15 seconds or less. and that's when panic struck and everybody started to run out. they were jumping on boylston street running toward the runners coming down boylston and running the other way trying to get away from that area. we ran into the area to see what had happened and it was then on the sidewalk i got a very good glimpse of what happened. there were a lot of people lying on the ground, nobody was screaming out and crying in pain. there was none of that. everybody looked as though they were completely dazed and the injuries were horrific. legs had been blown off. there was one image i have that burned in my mind, a small child

maybe five years old sitting up right, looked like he had been unarmed but at his feet was either his mother or father, leg blown off, their eyes were open but clearly they were checked out or completely shell-shocked and there was blood all over the sidewalk. within a matter of moments e.m.s., the police, volunteers with the race, they came racing in to try and get these people out and try to treat time on the scene and i'll set something else up for you. at the finish line of this marathon they have wheelchairs set up for runner runners who ce along the line fatigued, maybe they have a charlie horse or are having problems breathing. those wheelchairs loaded up people who were horrifically injured and they wheeled them down a block and a half to the triage tent and as they were wheeling them down they were wheeling them in front of spectators that are still wondering what has just happened and they saw with their own eyes because they didn't have blankets covering these people and it was a horrible scene. once they got into the tent they were treated.

ambulances came from all over the place and took them to the hospital. and now copley square, which is the heart of the back bay of boston, is completely closed down. the only people in here are emergency personnel. scott? >> pelley: jonathan, let's take a moment and other kwrepbt the folks at home about where these explosions occurred. we have a map of boylston street as we zoom into boston. at the bottom of your screen there is the finish line where the first explosion occurred. second explosion was about two blocks back down boylston street. jonathan, can you tell us what's at the scene of the second explosion? >> that's a great question, scott, because the first bomb is right by the finish line and by the time the bomb went off where we were in the race the crowd had started to thin. had that happened an hour earlier, they were ten deep in that part of the sidewalk but because the race had gone to almost the end you had maybe three or four people deep on that sidewalk. and then two blocks up the question you had asked, that is just spectators. they line boylston. i mean, literally for three

quarters of a mile that street is packed with spectators because it's the last leg of the race so people are always screaming and yelling and giving their support to the runners which helps them with their final cake to the race. it was just that area. they knew that would be the greatest number of spectators. that's why the area was targeted. i can say this: i don't know of any runners that were actually impacted by the bomb because the bombs were on the sidewalk and the sidewalk spectators and runners are blocked off by a fence and when they pulled that fence down we didn't see anybody on the street as far as runners. runners were knocked off their feet but we didn't see any runners taken away by ambulance because of the blasts. >> pelley: jonathan elias on boylston street for us tonight. jonathan, thank you very much. about 120 people are still in the hospital being treated for various wounds. they went to emergency rooms all over the city. don daylor is at massachusetts general. don? >> reporter: scott, the 129 victims were take on the seven area hospitals including mass

general here. they admitted 22, six of whom are listed in critical condition. among the more than a dozen around the boston area that are still clinging to life. and that's because of the nature of these injuries, these terrible, horrific injuries that doctors are describing as something you would see from a battlefield in afghanistan or iraq that we've -- soldiers have suffered for the past ten years or more. they are -- limbs blown off, traumatic head injuries. the youngest victim is a two-year-old boy. we can report that he is being prepped for surgery right now at boston's children's hospital. now, many of the victims didn't make it to the hospitals right away, but there's a good reason for that and that is because there were so many emergency workers on the scene at the race itself that they set up triage centers to treat them first, to stabilize them. they didn't want to rush them in here. they wanted to stabilize their systems and get them here safely. now, the tensions are still very, very high around this area, especially at the hospitals. at this parking garage behind me

a little while earlier swat teams were sweeping floor to floor because of a suspicious package and we are told that tufts hospital here in boston had to evacuate their emergency room for a little while when there was another suspicious package there. the one thing i should note, though, scott, despite the fact that so many of these victims suffered what doctors are describing as life threatening injuries, it should be noted that if they made it to the hospital so far no one has died there. >> pelley: don dahler at boston's mass general hospital. don, thank you very much. boston, of course, has some of the best hospitals and trauma centers in the country. dr. jon lapook has been talking with the physicians at the emergency rooms all afternoon. jon? >> well, they're doing exactly what they've been trained to do and, of course, there is the terrible physical toll for more than 100 people. but i'm especially worried about the emotional toll on the thousands of people who were there and the millions of people who have heard about it and are watching these images over and

over again. we know it can tremendously upsetting to have an event that's horrific and random over which they have no control, especially for kids. >> pelley: you've been talking to a number of the emergency room physicians. what were they seeing as they came through the door? >> they saw anything from shrapnel wounds, they didn't know whether it was shrapnel from a bomb but pieces of metal blown into people's legs, a leg that was blown off, glass injuries, eardrums that were burst and more serious injuries that led to somebody going up to the operating room and being operated on for a terrible injury to the leg. >> pelley: and we know that several children were also wounded in this. jon, thank you very much. we do not know who did this, whether it was terrorism inspired by a foreign source or domestically. it's very early in the investigation. but bob orr in our washington newsroom has been talking to his sources all afternoon and, bob, what are you hearing at this point? >> well, scott, the field is still wide open as to who might have done this and for what possible reason. the bombs don't appear to be very large.

i had one official say they didn't appear to be particularly sophisticated but keep in mind that's just guess work because they haven't forensically looked at it. the blast radius was relatively small but, still, in a crowd they did devastating damage. this doesn't appear to be the kind of work that al qaeda normally does. they normally go for something on a much grander scale. on the other hand, officials have pointed out to us this does have elements of coordination. there was more than one blast. so there was a coordinated plan. that may or may not mean more than one person was involved. it could be a very small cell. it could be a lone wolf inspired by either an international group or a domestic terror group or it could be someone acting out their own hostilities. we don't know yet, but the officials from the f.b.i., the a.t.f. and other agencies are doings a full court press, scott. >> pelley: bob, thank you. president obama at the white house today vowed to bring justice to whoever is responsible for the bombings. we will have that part of the story when the "cbs evening news" continues.

eight. i tried weight loss plans... but their shakes aren't always made for people with diabetes. that's why there's glucerna hunger smart shakes. they have carb steady, with carbs that digest slowly to help minimize blood sugar spikes. and they have six grams of sugars. with fifteen grams of protein to help manage hunger... look who's getting smart about her weight. [ male announcer ] glucerna hunger smart. a smart way to help manage hunger and diabetes. diarrhea, gas, bloating? yes! one phillips' colon health probiotic cap each day helps defend against these digestive issues with three strains of good bacteria. live the regular life. phillips'.

and "multiple choice," come to walgreens for help finding the one that's right for you... like centrum. now, get four dollars off select centrum products with balance rewards card. at the corner of happy and healthy. for over 30 years. and it's now the most doctor recommended, the most preferred and the most studied. so when it comes to getting the most out of your multivitamin, the choice is clear. centrum. >> pelley: we're back now with our continuing coverage of the terror attack at the boston marathon. we're told at this hour that the f.b.i. is now taking the lead in the investigation. president obama received several briefings at the white house today. this is a picture of him on the phone with the f.b.i. director robert mueller. the president then spoke to the nation from the white house briefing room and major garrett was there.

major? >> reporter: scott, the president did not describe the twin bombings in boston as an act of terrorism but moments after he left the briefing room a top white house advisor told us there is no doubt in the president's mind this, in fact, was an act of terrorism and he's ordered everyone in the federal government to treat it as such. this official told us the president did not want to get ahead of the evidence or the facts and his mandate to federal law enforcement is to work with law enforcement officials to build this case methodically so it can be prosecuted successfully. >> we still do not know who did this or why. and people shouldn't jump to conclusions before we have all the fact but mick no mistake, we will get to the bottom of this and we will find out who did this, we'll find out why they did this. any responsible individuals, any responsible groups will feel the full weight of justice. today's a holiday in massachusetts, patriots' day. it's a day that celebrates the

free and fiercely independent spirit that this great american city of boston has reflectd from the earliest days of our nation and it's a day that draws the world to boston's streets in a spirit of friendly competition. boston is a tough and resilient town, so are its people. i'm supremely confident that bostonians will pull together, take care of each other and move forward as one proud city and as they do the american people will be with them every single step of the way. >> reporter: the president is receiving regular law enforcement and counterterrorism briefings and, scott, the president also noted that the security has been increased in many cities across the country. he said that will continue as long as necessary. >> pelley: major, thank you very much. we will look at the terrorist attack again and speak with the man who shot the video when we come back. [ female announcer ] research suggests cell health plays a key role throughout our lives.

one a day women's 50+ is a complete multivitamin designed for women's health concerns as we age. it has 7 antioxidants to support cell health. one a day 50+. you'll have to pay five hundred bucks for your deductible. the truth? at allstate, you could pay zero. allstate gives you a hundred dollars off your deductible the day you sign up. then another hundred off every year you don't have an accident. let the good hands reward your safe driving with a deductible that goes away. ♪ deductible rewards. one more way you're in good hands with allstate. ♪ yeah by the time i do there's all these mystery stains. i mean is it coffee? could be gravy. yeah. so now i use tide boost with my tide. it's double powerful for when things get double iffy. [ female announcer ] together, tide and tide boost double your power against stains that's my tide. it's eb.

want to give your family the very best in taste, freshness, and nutrition? it's eb. eggland's best. better taste. better nutrition. better eggs. it's eb. [ sneezing ] she may be muddling through allergies. try zyrtec®. powerful allergy relief for adults and kids six years and older. zyrtec®. love the air. if you're suffering from constipation, miralax or metamucil may take days to work. for faster relief, try dulcolax laxative tablets. dulcolax provides gentle relief overnight unlike miralax and metamucil that can take up to 3 days. for predictable relief try dulcolax. and metamucil that can take up to 3 days.

>> pelley: back now with more on the attack at the boston marathon. we don't know who did this but it is clear that the bombs were calculated to kill and wound as many people as possible and to do so in one of the most photographed sports events in the world, the world-famous boston marathon. steve silva is a senior sport prose deucer at boston.com. he shot some of these images of the explosions that we've been showing you and steve is joining

us right now on the phone. steve, what did you witness? >> scott, i was on the finish line at 2:50 p.m. getting the runners coming across. there were over 9000 people still on the course. i was scared up right on the finish line and right off to my right out of the blue it was a loud thud noise and smoke went in the air tp-pbd for a split second you were wondering -- there were a few photographs, videographers, we ran toward the area and as we're running probably 20 seconds later the second bomb went off. so we knew you could immediately see the carnage and the people and the pools of blood and cuts from the marathon sports building glass blew out of the front window. and then of course pure chaos as you can imagine, we already had medical folks and the medical tent treating the usual marathon

runners and the cramps and stuff. there's involved in a triage situation scrambling. i saw one gentleman whose leg was severed at the knee and i know there are more injuries like that. >> pelley: there was stunned silence after the first blast then after 15 minutes the second. what happened after that? >> just police scrambling. there was mass confusion and people didn't know what the procedure was. the problem was the people that were injured in the blast were on the other side of the partition to keep them off of the race course so everyone had to pull the partitions away to get to the people and radio the people in the medical tent. all the roads were blocked off and the sidewalks were thick with about ten, 15 people so people were just running in every direction and didn't know which direction would go. it was pure chaos. >> pelley: steve silva, we will update you with the very latest information that we have when we come back in just a moment. from home repair to healthcare g

written by people just like you. no company can pay ngie's list, so you can trust what you're reading. angie's list is like having thousands of close neighbors where i can go ask for personal recommendations. that's the idea. before you have any work done, check angie's list. from roofers to plumbers to dentists and more, angie's list -- reviews you can trust. i love you, angie. sorry, honey. mr. wiggles and curling irons. for the little mishaps you feel, use neosporin to help you heal. it kills germs so you heal four days faster neosporin. also try neosporin eczema essentials. we don't let frequent heartburn come between us and what we love. so if you're one of them people who gets heartburn and then treats day after day... block the acid with prilosec otc and don't get heartburn in the first place! [ male announcer ] one pill each morning. 24 hours. zero heartburn. and "up to 75% lower copays."

as a preferred pharmacy, walgreens can save you as much as 75% compared to other select pharmacies. walgreens, at the corner of happy and healthy. the day building a play set begins with a surprise twinge of back pain... and a choice. take up to 4 advil in a day or 2 aleve for all day relief. [ male announcer ] that's handy. ♪

>> pelley: this bulletin just in from boston. the death toll in the terrorist attack there has now climbed to three. at least 120 people are being treated in the hospitals, many of them are in critical condition. also this evening. the f.b.i. has taken over as the lead agency in the

investigation. two bombs exploded within about two blocks of each other and just 125 seconds apart near the finish line of the marathon. it happened as runners raced past and spectators cheered them on. boston police say they recovered at least one other bomb that did not explode. president obama vowed that whoever is responsible will, in his words, "feel the full weight of justice." much of downtown boston remains sealed off tonight the area still a crime scene. some cbs stations will be leaving us now for local programming. for many of you the "cbs evening news" will continue in just a moment. you kids should count yourselves lucky.

we didn't have u-verse back in my day. you couldn't just... guys... there you are. you know you couldn't just pause a show in one room, then... where was i... you couldn't pause a show in one room then start playing it in another. and...i'm talking to myself... [ male announcer ] call to get u-verse tv for just $19 a month for 2 years with qualifying bundles.

for those of you just joining us this is a special expanded edition, part of our cbs news continuing coverage of the terrorist attack at the boston marathon. we have just learned moments ago that a third person has died. two bombs went off near the end of the race has runners were making their way to the finish line. what was to be a moment of triumph turned to a tragic, tragic event this evening. besides the three dead, more than 120 were hurt, some of them critically, at least one device did not explode and was recovered by police. but there is conflicting information about that tot